And nicholas o connell



UNITED STATES PATENT OFFICE,

MOSES B. TIOE, OF NEWARK, NEW JERSEY, AND NICHOLAS OOONNELL, OF BROOKLYN, NEW YORK.

PROCESS FOR FINISHING LEATHER.

SPECIFICATION forming part of Letters Patent No. 225,772, dated March 23, 1880.

' Application filed August 1, 1878.

To all whom it may concern Be it known that we, Mosns B. Tron, of Newark, in the county of Essex and State of New Jersey, and NIonoLAs OGoNNELL, of

Brooklyn, in the county of Kings and State of New York, have invented a new and Improved Process of Finishing all kinds of Leather; and we hereby declare the following to be a full, clear, and exact description of the same.

Our invention relates to that class of processes employed for finishing leather.

Heretofore, in preparing leather for market, metallic salts have been used, and, with other chemical compounds and-dyes, been made to 1 combine with the substance of the leather for the purpose of rendering the material impervious to moisture, and thus to strengthen the fiber and give it a suitable color and finish for the various manufacturing purposes; but the fiber of leather not being readily absorbent of compounds containing metallic salts, the beneficial effect of the treatment has been confined to skins or leather of the higher grades of quality only, and so far with only partial success even as to them, as the material has been found not to retain permanently the metallic salts or color of the dye, and is liable to exude, the metallic salts and coloring-matter, thus injuring the appearance of the leather 0 and causing the color to fade and the leather to crack, thus rendering the present methods only partially successful, and objectionable on account of the higher grade of skins it is applicable to and the want of permanence in 5 finish.

The object of our invention is to provide a process for finishing leather which will render the fiber of the leather of all grades more absorbent of the chemical. compounds and dyes,

and will also set and retain the color and the metallic bases of the compounds used, and give a durable and satin finish to leather of all grades, and make the lowest grades susceptible of a finish equal to the best morocco 5 leather.

In order to enable others to use and practioe our invention, we will proceed to describe the same and the operation.

Our invention consists in the previous use of certain preparatory solution and dyeing co1npounds, in combination with a secondary and a perfecting compound applied and used in the manner and order and composed of theingredients as hereinafter set forth, one essential requisite of this process being that the treatment shall be followed strictlyin the order as here designated.

For the first part of our process, after the leather has been tanned and shaved in the ordinary way, saturate with a liquid compound composed of a hot solution of logwood made by boiling ten pounds of logwood-chips in forty-five gallons of water until reduced to twenty-five gallons, which we designate our preparatory solution. Second, the leather 6 is then put on tables for stretching and taking the water out, then hung up and partially dried. Third, sammy it, then put out on the tables the second time. Fourth, if it is 1110'- rocco and required to be straight-grained or pebbled, do so by the use of hand-board or machinery. Fifth, it is then blackened by the use of a liquid compound composed of a solution of iron, vinegar, and animal-blood, either warm or coagulated, made by suspending eight 7 5 pounds of iron in forty (40) gallons of vinegar, thirty grains test,for three weeks; and to one quart of this solution add a half a pint of animal-blood, either warm or coagulated, and this application is sometinies repeated; then hang up the skins and allow them to dry; or the leather may be blackened by dyeing in trays, by saturating'with a liquid compound composed as follows: Say copperas, one pound; nitrate of iron, one pound; verdigris, onehalf 8 5 pound; chromate of potash, two ounces; Sicily sumac, two pounds; soda -ash, .one -fourth pound; pulverized nut-gall, two pounds; water, forty gallons- To color leather buff and grain it, add to this last solution four ounces of anio mal-blood to the quart, and put it on with brush or sponge on the table. Sixth, if a bright finish is desired, glaze with the glazingmachine or on the table with a glass or flint.

If a dull finish is desired, do not glaze, but 5 brush on the face with a brush. Seventh, soften on the table by use of board or slicker. Eighth, oil the face of the leather, after which the process is continued as follows:

For the second part of our process we use a chemical compound which consists of, say, one part of dry gelatine (isinglass or other) dissolved in four parts of oil, including a small quantity of sulphuric or other acid, and when these are combined bymeans of heat, five parts, or thereabout, of an alkaline solution of canstic soda are added at a specific gravity of about 26 Baume, the whole being stirred while yet warm, and the result is a chemical combination which we designate the secondary compound.

For the third part of the process we use a chemical compound which we designate the perfecting compound, and which is prepared as follows, namely: In one vessel is prepared a strong solution of one of the alumsfor instance, of the sulphate of alumina-with potassa or either ammonia or soda as equivalent. In another vessel is prepared a solution of the sulphate of zinc, and in a third vessel a solution of the acetate of lead. These solutions are each to be of the same density. When prepared the two sulphate solutions are mixed in the proportions of about five parts of the first named to one and a half part of the latter named, and to these are added about five and a half parts of the acetate-of-lead solution. By the chemical action that ensues sulphate of lead is formed, and when this has subsided the clear liquid is drawn off and is reduced to the proper density, which is 1 to 2 Baum.

The manner of continuing the treatment of leather to be finished is as follows: A bath is prepared with, say, half an ounce of the secondary compound dissolved in two gallons of hot water-that is, in about these proportions. This is used when cold. To treat leather we steep it in this bath till endued with its properties and then drain it. WVhen the leather has been removed from the bath of the secondary compound and is well drained, we steep it in a bath of the perfecting compound, where it remains from eight to twelve hours, and when well drained it is gradually dried, which completes the finishing process. After the finishing the process is thus complete, the leather is again softened by use of board or slicker, then oiled to bring the color out and make it soft and pliable, and properly prepared and ready for manufacturing purposes. This finishing process gives to leatherof all grades a satin finish superior and more durable than anything heretofore known and used.

The preparatory solution, by being first applied when the liquid compounds for coloring are afterward applied, set the color at once, and require but one-half of amount of coloring-matter heretofore used, which is very beneficial to the leather, for the reason that the less coloring-matter used the stronger is the leather, and by thus coloring before using the other finishing compound, which has never heretofore been done, the color is fastened, and will never fade or come out.

What we claim, and desire to secure by Lettcrs Patent, is

The herein-described process of treating or finishing leather, which consists, first, in subjecting it to the action of a solution of logwood and water, and then stretching, drying, sammying, pebbling, blackening, and dyeing, as usual; secondly, treating the leather with arsolution of gelatine, oil, acid, and an alkaline solution of caustic soda; and, finally, subjecting the leather to a solution of sulphate of alumina, potassa, or its equivalent, as described, sulphate of zinc, and the acetate of lead, all as herein described, the whole formin g a complete and continuous process, as and for the purpose set forth.

- MOSES B. TiCE.

NICHOLAS OOONNELL. Witnesses:

.B. F. SAWYER, JOHN H. MURRAY. 

